Field of the Invention
The invention relates to a method for data communication between at least one mobile operating unit and at least one field device. Furthermore, the invention relates to a communication arrangement for data communication between at least one mobile operating unit and at least one field device. Finally, the invention is related to a gate device having at least one input interface and at least one output interface.
Description of Related Art
In modern process automation, it is often typical to monitor processes or media, in that measurement variables are determined, in particular, using field devices in the form of measuring devices, or to monitor in respect to changes. Thus, it is known, for example, to determine the flow of a flowable medium through tubes or channels, in that, for example, measuring devices are used that operate according to the Coriolis or vortex method, in which ultrasonic signals are used or which determine the flow using calorimetry.
In order to determine the fill level of a medium, which can be a liquid or a bulk material, it is known from the prior art to evaluate the transit time of electromagnetic signals using the radar method, or more specifically using the TDR method. The Doppler Effect can also be applied, or plumb lines are used. Furthermore, there are many designs for recognizing certain fill levels, either capacitively, inductively or by using elements capable of swinging.
In order to obtain further information about the media or processes, measuring devices are also used, with which pH, temperature, viscosity, electric conductivity or electric resistance are measured.
On the other hand, field devices are used that allow for intervention in the corresponding process. Such field devices are called actuators or control elements. An example of such is valves that allow for the regulation of a medium being filled and/or drained. Furthermore, a field device can also be an element that affects the temperature, for example, in that it heats. Additionally, an actuator can be a stirring device.
In order to be able to optimally supervise, control and regulate complex processes, field devices are generally in contact with a control room (also called control station, switch room or measuring station), which are thus part of a process control system (PCS).
In the field of industrial application, so-called fieldbuses having corresponding protocols are often used for contact between field device and control room. Contact with cables or without cables, e.g., wireless, is known. Common fieldbuses or protocols are Ethernet, foundation fieldbus (FF), Profibus DP or PA, Modbus, etc.
Data from field devices is transmitted to the control room from the field devices or data, e.g., parameter values, or software components, etc., is received by the field devices from the control room.
This also means that many field devices do not allow direct access, but communicate only with the control room.
For this reason, many field devices have neither their own display device (also called display) nor an input device, e.g., in the form of a keypad or a minimal configuration of keys (e.g., arrow key+confirmation key).
However, many field devices have so-called human machine interfaces (often abbreviated to HMI, or also user interface) that allow a direct display of e.g., the measured value or also allow direct influence on the particular field device.
Some field devices have interfaces that allow e.g., the application of software or firmware even in field devices already installed in the process, or allow the access to deeper layers of the field device for specially trained staff. Such interfaces are sometimes so-called service interfaces.
In order to make working with the field devices possible or simpler for operating staff, it is also known to use so-called handhelds.
These mobile—i.e., mostly portable—hand devices allow, at least in part, immediate contact directly with a field device or they can be directly connected to the field device in order to influence the field device or, for example, to read data via this connection.
The parameterization of different field devices occurs, for example, by using special device description language (DDL) data files.
Since field devices from different producers, and even sometimes from the same producer, require different programs, access data, data processing possibilities, etc., it is possibly thus necessary to have to use different hand devices or for the hand devices to have correspondingly large libraries of control data or programs or other access data or programs.
In addition to the costs for hand devices, it is often a disadvantage that such devices are more complicated in operation or do not offer the ease that the operating staff is used to from their experiences as consumers, in particular in comparison to modern consumer electronics. An example of such is the rather intuitive handling as is common in modern, so-called smartphones.
It is common in so-called smartphones, to load so-called apps (abbreviation for application software), which allow special applications on the smartphone.
The simpler handling from the field of consumer (also user) electronics has not yet found access into the field of process automation or, more specifically, the interaction with individual field devices.
However, especially in the case of data communication between a mobile unit and a field device that is installed in a process system, it would be advantageous if at least the interaction with the mobile operating unit were as simple as possible. The reason for this is that the operation of such process systems is usually rather unpleasant for the operating staff (e.g., very high or very low temperatures, extreme humidity or air dryness, irritating noise levels, or unpleasant odors, etc.).
Furthermore, careful handling of the field device itself requires a high measure of concentration, so that the tools used (here, in particular, the mobile operating unit) should be as simple as possible.
If the operating staff is faced with a field device with the task of creating an at least generally temporary communication arrangement for data communication between the mobile operating unit and the field device, then, depending on the specific application, data is entered into the field device via the operating unit or data is received by the field device.
The data entered is, for example, a parameter for measurements by a measuring device as field device or for influencing the process using an actuator as field device. Further possibilities are calibration data or other correcting data. Alternatively or additionally, it is software or firmware that is installed in the field device.
On the other hand, there are applications, in which the mobile unit receives data from the field device. This is, for example, current measured values or history data. Furthermore, it can also be relevant to read data, with which the field device operates, such as, e.g., the version number of the software used, etc. Finally, depending on the specific application, access of a mobile operating unit to a field device allows for storage of data associated with previous access to the field device.